/Engine/Source/Runtime/MovieScene/Public/Evaluation/MovieSceneEvaluationTree.h
Adds a new time range with the associated data to the tree, only for segments where there's no data yet.
void AddIfEmpty ( [TRange](API\Runtime\Core\Math\TRange)< [FFrameNumber](API\Runtime\Core\Misc\FFrameNumber) > InTimeRange, [DataType](API\Plugins\OptimusCore\DataType) InData )